All five rovers that the Soviet Union and the U.S. left on the moon in the 1970s have been found by a NASA orbiter—and three are still used today for gathering data.

The 5 Cars That Wheeled Across the Moon

The 5 Cars That Wheeled Across the Moon

NASA's Lunar Reconnaissance Orbiter (LRO) headed to the moon in June 2009 with a camera system and a suite of other instruments it would use to measure the surface. The LRO's high-resolution images would build maps far more detailed than those used by the Apollo missions. In fact, it even spotted the relics of those missions: rovers left by the Apollo and Soviet Luna missions in the 1960s and 1970s.

There are five cars on the moon, still sitting there 40 years after their heyday. The Soviets were the first to do it. In 1970, the Luna 17 spacecraft landed a remote-controlled, eight-wheeled, seven-foot-long car on the moon. Later, the U.S. one-upped the USSR by landing three manned vehicles on the surface. In 1971 and 1972 Apollo 15, 16, and 17 carried 10-foot-long LRVs (lunar roving vehicles). The final rover to land on the moon was from the Soviet Luna 21 mission in 1973.

On the earlier Apollo missions, astronauts on the moon had to pull wheeled carts full of equipment to drill and sample soil and set up cameras and antennae. The NASA rovers used mounts for equipment, and allowed the astronauts to venture farther away from their landing-module base camps. These rigs were vital to both the Soviet and U.S. space programs. Here's a deeper look at the five rovers that first landed on the surface of the moon and their missions.

Lunakhod 1

Lunakhod 1

In November 1970 the Soviet spacecraft Luna 17 touched down on the moon and deployed a ramp; then the seven-foot-long, five-foot-tall Lunakhod 1 remote-controlled rover drove onto the surface. Lunakhod 1 used eight electrically powered wheels and carried equipment such as cosmic-ray detectors and spectrometers. It hauled along four video cameras and antennae that sprouted from the bathtub-like body of the rover to transmit video back to Earth. The antennae also received commands from the scientists on Earth who operated remote arms to collect samples, examine the moon's surface, and send photos back.

Solar cells powered all the equipment; they received a long charge during the lunar daytime (equal to about 13 earth days). The rover then hunkered down for the very long, very cold night. A small nuclear heater kept Lunakhod 1 from freezing every night, when temperatures would drop to minus 240 degrees Fahrenheit.

The Soviet scientists planned on Lunakhod 1 operating for about three spells of lunar daytime (about 40 earth days of operational time, not counting the lunar nighttime when the rover slept). But the remarkable unit lasted almost four times as long, until September 1971, and covered about 10 kilometers (6.2 miles) during that time. When it finally lost touch with its earthbound operators, Lunakhod 1 had performed hundreds of geological tests and sent back thousands of photos. It had wandered into an area invisible to telescopes on Earth. In fact, its exact final location was a mystery until March 2009, when NASA's LRO cameras spotted it.